-LRB- CNN -RRB- -- The small plane had crashed in an extremely remote part of Alaska , miles from the tiny village of St. Mary 's .

It was an especially dark and foggy Friday night , and rescuers were having a hard time figuring out the location of the Cessna wreckage and its 10 passengers .

They could hear survivor Melanie Coffee on the phone but with the poor weather , it was a frustrating needle-in-a-haystack kind of task .

But Coffee , 25 , made her way a half-mile across the slippery , sloping tundra and managed to find the town 's landfill , where she met the search party of 40 to 50 villagers and calmly guided them on foot back to the crash site .

For four people , including her 5-month-old boy , it was too late . They had died from their injuries .

The others had wounds that included head injuries and multiple fractures .

Had it not been for her going for help , more victims might have died , said Clifford Dalton , a paramedic for LifeMed Alaska .

`` The fact that she could make it out to an identifiable landmark really helped to expedite the aid that the rest of the patients were able to receive , '' Dalton said . `` What 's really remarkable about it is that she was tending to her infant child that was gravely injured at the time . ''

The Anchorage Daily News reported that after the crash , Coffee used a cell phone to call the on-call health aide for St. Mary 's , population 500 . Fred Lamont Jr. told the newspaper Coffee was trying to give her infant son CPR .

Dalton called Coffee a hero who put the needs of others before her own .

Dalton said he and his partner , Paul Garnet , helped treat the patients at the site . Six to eight villagers helped carry each survivor to the landfill , which was as close as the ambulances could get . Concerned residents also came to help from Mountain Village , about 25 miles away , where most of the victims were from .

Authorities are unsure why Hageland Aviation Flight 1453 crashed . It left Bethel at 5:40 p.m. and went down about four miles from the St. Mary 's airport .

`` Hageland is working to gather information to answer questions and do what we can to ease the suffering of those involved in the accident . As a family-owned business this is an unspeakable tragedy for us , '' company president Jim Hickerson said on Hageland 's Facebook page .

Authorities said the dead were Wyatt Coffee , 5 months ; pilot Terry Hanson , 68 ; Richard Polty , 65 ; and Rose Polty , 57 .

Four of those injured were hospitalized in fair condition , officials said . They are : Pauline Johnson , 37 ; Shannon Lawrence -LRB- age not given -RRB- ; Tanya Lawrence , 35 ; and Garrette Moses , 30 . Also injured was Kylan Johnson , 14 , who was treated and released .

A spokeswoman for the the Alaska Native Medical Center said Melanie Coffee was in fair condition and was n't giving interviews .

The National Transportation Safety Board said Sunday it was too early to determine if weather was the cause .

Alaskans depend on air transportation far more than residents in other states because many villages are n't on the road system .

About 35 % of commuter plane and air taxi crashes in the United States between 1990 and 2009 occurred in Alaska , according to data compiled by the Centers for Disease Control and Prevention .

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CNN 's Paul Vercammen , Stan Wilson , Karan Olson and Joe Sutton contributed to this story .

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Melanie Coffee walked through the night over sloping tundra to reach rescuers

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She then guided them back to the site of a small plane crash where four people were dead

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The dead included her infant son , who she tried to give CPR , according to newspaper report

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Five other people were injured